Multiple filament electric lamp



April 1943- H. a BUTLER 2,317,027

I MULTIPLE FILAMENT ELECTRIC LAM? I V 7 Filed April 18, 1942' Invervtov: Hem E. Bu'fler, y v Mm His Ac'ltorneg.

Patented Apr. 20, 1943 MULTIPLE FILALIENT ELECTRIC LAMP Henry E. Butler, Scotla, N. Y., assignor to General Electric Company, a. corporation of New York Application April 18, 1942, Serial No. 439,602

8 Claims. (Cl. 176-26) My invention relates to electric incandescent lamps and more particularly to multiple filament lamps.

An object of my invention is to provide a simplified multiple filament lamp wherein provision is made for readily replacing or substituting a second filament for a first filament. To this end the lamp preferably comprises means for removably supporting a filament and conducting current thereto, and a second filament which is so designed and supported in the bulb of the lamp that it may be transferred bodily onto the said supporting and current conducting means t place the first-mentioned filament. One of the features of my invention is the provision of an arrangement whereby the said second filament may be transferred by means of a magnet. Further features and advantages of my invention will appear from the following detailed description of a species thereof and from the drawing.

In the drawing, Fig. 1 is a perspective view of a lamp comprising my invention, together with a magnet for transferring the second or auxiliary filament, and Fig. 2 is an elevation showing an alternative method of supporting a filament.

Referring to the drawing, the lamp comprises the usual glass bulb I and base II. A pair of lead-in wires I2, 12 extend into the bulb through the press portion I3 of the usual stem I4, and are connected at their outer ends to the shell and end contacts of the base II. The inner ends of the lead-in wires I2, I2 are provided with hooks i5, 1,5. A filament IE, preferably of tungsten, is supported by the hooks I5, I5. The said filament has straight end portions I1, H which engage the hooks IE, IS and may consist of one of the metals commonly used for lead-in wires, although they may, if desired, be continuations ofthe filament itself. Attached to each end of the filament, or to the end portion I'I thereof, is a disc I8 of magnetizable metal such as steel.

A second filament I6 is also located in the-bulb I0 and it may be similar in design to the filament l6. As shown in the drawing. the second filament I6 is merely disposed loosely within the bulb I0 and is supported by the bulb.

Upon failure of the filament I 6, the second filament I6 may be transferred onto the hooks I5, by means of a magnet I9 which acts on the magnetizable discs I8, I8.

-While I have shown and described one species of my invention, it will be obvious to those skilled in the art that various modifications may be made therein. It will be understood that, if delower or higher candle power than the filament I6, and the filaments I6 and I6 may be interchangeably mounted on the hooks I5, I5 to provide a lamp which emits difierent levels of illumination. To this end, the lamp may be provided with additional hooks, similar to the hooks I5, I5 for supporting the filament I6 when the filament I6 is to be substituted therefor in the hooks I5, I5.

As an alternative method of supporting the filament on the lead-in wires I2, 12, I may replace the hooks I5, I5 with small permanent magnets 20, 20 (Fig. 2) such as Alnico magnets, and make the end portions I1, ll of magnetic metal. With such a construction, in the event the master magnet I9 is not available, the renewal filament I6 with its magnetic metal end portions 11', I1 may be placed on the faces of the small magnets by properly manipulating the lamp.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric incandescent lamp comprising a bulb containing a filament, means for removably supporting said filament and conducting cur rent thereto, and a second filament in said bulb physically separate from said supporting and ourrent conducting means and from said first mentioned filament and capable of being transferred bodily onto said supporting and current conducting means to replace said first-mentioned filament. I

2. An electric incandescent lamp comprising a bulb containing a filament, means for removably supporting said filament and conducting current thereto, and a second filament in said bulb capable of being transferred bodily onto said supporting and current conducting means to replace said first-mentioned filament, said second filament having secured thereto members of magnetizable metal by means of which the v filament may be picked up by an external magnet.

sired, the filament I6 may be designed for a 3. An electric incandescent lamp comprising a bulb, a pair of lead-in wires extending into said bulb and having hook-shaped end portions, a filament supported by said hook-shaped leadin wire end portions without being secured thereto, and a second filament in said bulb spaced from said lead-in wire end portions and physically separate from said first-mentioned filament and capable of being transferred bodily onto said hook-shaped lead-in wire end portions to replace said first-mentioned filament.

4. An electric incandescent lamp comprising a bulb, a pair of, lead-in wires extending into lead-in wire end portions to replace said firstmentioned filament, said second-filament having discs or magnetizable metal secured to its ends by means of which the filament may be picked up by an external magnet.

5. An electric incandescent lamp comprising a bulb, a pair 01 lead-in wires extending into said bulb and having hook-shaped end portions, a filament supported by said hook-shaped lead-in wire end portions without being secured thereto, and a second filament in said bulb capable of being transferred bodily onto said hook-shaped lead-in wire end portions to replace said firstmentioned filament, each of said filaments having discs of magnetizable metal secured to its ends by means of which the filaments may be picked up by an external magnet.

6. An electric incandescent lamp comprising a bulb containing a filament having end portions of magnetic material, means for removably supporting said filament and conducting current thereto comprising permanent magnets engaging.

,end portions ot'magnetic material.

v 7. In an electric incandescent lamp, 8. filament having end portions or magnetic material, and means for supporting said filament and conducting current thereto comprising permanent mag- HENRY E. BUTLER. 

